In an analysis method, reaction liquid obtained upon reaction of a sample and a reagent is analyzed by an optical technique, for example. In such a method for analyzing a sample, use is made of an analytical tool for providing a reaction field. For example, there exist analytical tools which are designed to remove solid components in the sample liquid before the sample liquid is supplied to reagent portions. Examples of such analytical tools include one shown in FIGS. 13 and 14 and one shown in FIGS. 15 and 16 of the present application (See JP-A 2002-508698A and JP-A 8-114539, for example).
The analytical tool 9A shown in FIGS. 13 and 14 includes a substrate 90, a cover 91, and a filter 92 interposed therebetween. The substrate 90 is formed with a space 90a in which the filter 92 is fitted. The cover 91 is formed with a liquid introduction port 92a located above the filter 92. The filter space 90a is connected to a discharge region 90b. In the analytical tool 9A, liquid is introduced through the liquid introduction port 92a to the filter 92 for removal of solid components and then guided to the discharge region 90b. 
The analytical tool 9B shown in FIGS. 15 and 16 includes a sample receiving port 93, a first sample treatment chamber 94 for removing a substance causing measurement error, a first measurement chamber 95 for measuring a pre-reaction value, a second sample treatment chamber 96 including a reagent portion for reaction with a target substance, a second measurement chamber 97 for measuring optical characteristics of a reaction product of the target substance and the reagent, a filter 98 provided in the first sample treatment chamber 94 and directly below the sample receiving port 93, and a pump connection port 99. In the analytical tool 9B, a sample liquid is introduced through the sample liquid receiving port 93 to the filter 98 for removal of solid components and then guided to the first sample treatment chamber 94. With a pump connected to the pump connection port 99 of the analytical tool 9B, the sample liquid is sucked by the motive power of the pump for movement through the chambers 94-97.
In the analytical tools 9A and 9B, the removal of solid components at the filters 92, 98 is performed mainly when the sample liquid moves in the plane direction of the filters 92, 98. Therefore, in the analytical tools 9A and 9B, a large filtration length can be attained, so that efficient removal of solid components is expected. On the other hand, however, there is a fear that the removal of solid components takes long time and the measurement time becomes long due to the large filtration length and a long retention time of the sample liquid in the filters 92, 98. Such a fear is serious in an analytical tool designed to move a sample liquid by utilizing capillary action. Moreover, in such an analytical tool as a microdevice which has a flow path of a small sectional area, the movement of a sample liquid through the small flow path by capillary action becomes difficult when the sample liquid has a high viscosity. In such a case again, the above fear is serious.
When a sample liquid is moved by utilizing motive power of a pump as is in the analytical tool 9B, the sample liquid can be moved relatively easily, so that the above fear relating to the measurement time is not serious. However, since the apparatus for performing analysis by using the analytical tool 9B need be provided with a pump, the cost for the apparatus increases correspondingly. Moreover, the use of the pump increases the cost required for a single time of measurement.